1. Field of the Invention
The invention relates to a karaoke music reproduction device which uses digital signals for the control of a MIDI sound source while at the same time generating a synchronous display of lyric related data expressed in character, graphic or some other form on a visual display medium. The invention relates more particularly to a technique for the selection, by a means other than the lyric display means, of images to match the mood of the music and the subsequent display of said images on the display screen along with said lyrics.
2. Description of the Prior Art
There are well known techniques relating to the use of a sound source in the creation of music in accordance with the MIDI standard and the subsequent reproduction of said music. The fact that karaoke music is essentially a musical accompaniment with the vocals cut out also facilitates the reproduction of such music through a MIDI sound source. The inventors formerly disclosed the technology involved in the above aspects of karaoke music in U.S. Pat. No. 5,046,004 and U.S. Pat. No. 5,127,303. It is also necessary, for karaoke purposes, to supply the user with the lyrics of the songs he wishes to perform and the most recent trend has been to display said lyrics on a visual display medium in time with the music. Techniques for the display of lyrics are also covered by the disclosures of the patents referred to above. Clearly, then, it is perfectly possible to use this sort of technology to create audio signals through the medium of a MIDI sound source and then to pass said signals through an amplifier to a speaker for reproduction in the form of music. At the same time, it is also clearly possible to display song lyrics in time with said music. Moreover, since the use of MIDI data enables a very significant reduction in the amount of data required compared with, say, PCM recording, it is also possible to transmit the required data from a host computer via a public telephone line to a user's terminal unit for reproduction using the techniques developed by the aforementioned inventors.
However, if the data is structured such that it contains only MIDI data and lyric data, then this quite naturally means that nothing other than the song lyrics can be displayed on the display screen and this in turn precludes the background display of dynamic images which again represent a mode of karaoke music presentation which is also becoming very popular these days. It has thus become necessary, from the presentational point of view, to provide dynamic images as a background against which song lyrics can be displayed. Dynamic images, however, require a much larger volume of data than do either MIDI data or lyric data and, if the whole of this volume of data is to be transmitted by public telephone line, then the download operation will itself take much too long. In other words, the adverse effect on the data transmission operation is due not to the essential MIDI and lyric data but to the inclusion of incidental image-related presentation data. Since, therefore, in the final analysis, dynamic images represent nothing more than an embellishment of the presentation of karaoke music, it is better to structure them quite separately from the music itself. A further problem is that, if the dynamic images are, in fact, incorporated into the basic music and lyric data then they must also necessarily become fixed in their relationship to the music and there is thus an obvious danger that the dynamic background images might eventually lose their visual impact on the user.